One vertex per element, one color per generator, with an edge from x to x·s.
(1,2,5,4)(3,7,8,6)(9,10,14,15)(11,18,16,12)(13,17,22,23)(19,21,24,20)(25,26)(27,29)(28,33)(30,35)(31,36)(32,34)(37,38)(39,40)(1,3,5,8)(2,6,4,7)(9,10,14,15)(11,12,16,18)(13,17,22,23)(19,20,24,21)(25,27,31,34)(26,32,36,29)(28,35,39,37)(30,33,38,40)(10,15)(11,16)(17,23)(19,24)(25,28)(26,33)(27,37)(29,38)(30,32)(31,39)(34,35)(36,40) involution — undirected(9,11,14,16)(10,12,15,18)(13,19,22,24)(17,20,23,21)(25,29,31,32)(26,34,36,27)(28,38,39,30)(33,35,40,37)(1,4,5,2)(3,7,8,6)(9,12)(10,16)(11,15)(13,21)(14,18)(17,19)(20,22)(23,24)(25,30,31,38)(26,35,36,37)(27,33,34,40)(28,32,39,29)(9,13)(10,17)(11,19)(12,20)(14,22)(15,23)(16,24)(18,21)(25,26)(27,32)(28,33)(29,34)(30,37)(31,36)(35,38)(39,40) involution — undirectedA Cayley diagram is a choice, not a fact about the group. Another drawing of this group — in a book, or on a different generating set — may look nothing like this one.